Method of making scraper-bowls.



PATENTED MAR. 6, 1906.

. T. H. ST'AGG. METHOD OF MAKING SGRAPER BOWLS.

APPLICATION FILED OUT. 15, 1904.

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' A W W Nd. 814,568. PAT-ENTED MAR. 6, 1906. T. H. STAGG.

METHOD OF MAKING SGRAPER BOWLS.

PPPPPP ATION FILED OCT. 15, 1904.

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APPLICATION FILED 0OT.15, 1904.

3 SHEETSSHEET 3.

NITED STATES PATENT oEEIo THO-MASH. sTAoe, or COLUMBUS, OHIO, ASSIGNOR To THE KILBOURXE & JACOBS MANUFACTURING COMPANY, or COLUMBUS, omo, A COR- PORATION OF OHIO.

. METHOD oF IVlAKlNG SCRAPER -BOWL S.

Specification of Letters Patent.

, Patented March 6, 1906.

Application filed October 15, 1904. Serial No. 228,570.

To all whom it may concern:

Be it known that I, THOMAS H. STAGG, a citizen of the United States, and a resident of Columbus, in the county of Franklin and State of Ohio, have invented certain new and useful Improvements in the Manufacture of Scrapers, of which the following is a specification.

My invention relates more particularly to the production of the bowls or bodies of scrapers by stamping sheets of steel of suitable dimensions between dies.

The method heretofore practiced in the production of stamped steel scraper-bodies consists in providing an open-ended lower or hollow die conforming to the shape of the bowl to be produced, placing thereon a steel sheet of proper dimensions with one edge of the sheet across the open end, of the die, placing a clamping-frame over the sheet to hold its edges, and then dropping. orpressing upon the sheet the up er die to force the sheet into the lower die; but this method involves a number of disadvantages both in the method ofprocedure and in the article produced.

My present'invention provides a method of producing scraper-bowls by which these disadvantages both in the method of production and article produced are entirely avoided and by which the economy of production is greatly increased and the wearing qualities of the article improved.

The several features of my invention will be understood upon reference to the accompanying drawings, in which I Fi e 1 is a perspective view of the upper and ower dies and the clamping-frame utilized in practicing my invention, the parts beseparated to receive a sheet of steel between them. Fig. 2 is a vertical longitudinal section, on an enlarged scale, sho the same arts with the clamping-frame ho ding trated in Figs. 2 and 3. 0

the e ges of the sheet, the dies forced together, and the sheet pressed into shape. Fig. 3 is a vertical section of the same on the line 3 3, Fig. 2, being in a plane at right angles to the plane of Fig. 2. Fig. 4 is a perspective view of the blank-formed by the step illus- Figs. 5 and 6 are a side elevation and a to plan of the same with the holding flan e or rim of the original sheet trimmed off. l ig 7 is a perspective of the finished scraper-bowl. Figs. 8 and 9 are peranincurved front edge, trimming back of the deepest point of the eral objections encountered in the manufacture of scraper-bowls by the single process.

cient y tight to cause-the metal to stretch some.

In manufacturing scraper-bowls by the old method, in which the sheet was placed over an open-ended die, if, on the one hand, the clamping-frame is pressed on the rim of the sheet with any considerable force the sheet usually tears at or near the points a in Fig. 8, and the scraper-bowl must be trimmed on such lines as to eliminate the defect in order to obtain a marketable im lenient. This results in great loss of materia red uction in capacity of the bowl, ununiformityin theproduct of the dies, and withal a great increase in cost of manufacture. If, on the other hand, clamping pressure on the forward end of the frame is modified sufficiently to permit the metal to slip before tearing, the metal is crimped or buckled proportionally to the inclination of the sides of the die or the reduction of its width'where the sides meet the bottom, the portion of the sheet which is first stretched across a wider portion of the die being subsequently crowded into a more restricted port on, and we have an imperfect front cutting edge, as indicated at bin Fig. 9. I In both of these cases, Figs. 8 and '9, the metal draws spective views illustrative of two of the sev-" lar ely from the front edge to fill in the deep hee of the scraper-bowl, and this results in which necessitates curve to produce a marketable article.

,The main features of my invention, bv means of which I am enabled to overcome all of the aforementioned difficulties, consist in so sustaining the metal'of the sides a ainst tearing at the points a that the meta may be safely stretched in stamping sufiiciently to insure a smooth cutting end in each scraper-bowland in so' sustamin the metal of each scraper-bowl longitudina ly that the metal for the deep heel willnot be drawn from the portions constituting the fronts of the ultimate scraper-bowls, except as stretching may yield some metal toward the heel.

In carrying out my invention I employ a pair of dies A B, Fig. 1, and a holding clamp or frame C of proper form and dimensions to produce a blank D, Figs. 4 to 6, of two scraperbowls d, joined at their open forward or cutting ends e, the sheet from which this blank g and suitably connected with the frameand this pressure is so regulated that the sheet may not slip freely in yielding the metal necessary to form the vertical walls of the blank; but this yield of metal is resisted sufficiently to stretch all of the parts and insure thoroughly smooth work, not only throughout the main body'of the bowl, but along that portion of the blank which is to form the open fronts and cutting edges of the bowls. There being no vertical edges in the plane on which the division of the two bowls is to take place, tearing does not occur and the metal is accordingly stretched here as in the other parts. The longitudinal pull resulting from forming the heels is balanced in the two symmetrical ends of the blank. Hence no distortion occurs.

After producing the double-bowl blank the flanges f may be trimmed off to produce the blank shown in Figs. 5 and 6, after which the two bowls are severed on the transverse line a; and each half. then trimmed on the curved lines y to produce two finished bowls like that shown in Fig. 7. To further improve the re-. sults of the process, as well as to obtain an advantageo'us shape in the finished article, the lower die has a middle ridge K, over which the metal is stretched and smoothed, and which gives to the finished bowl an upwardly-in'clined forward end that retains the contents of the bowl when filled and while carrying to the place offdurnping. This: also reduces the cutting necessary to sever the bowls and trim them after separation.

The process is important for other considerations than those above mentioned. The labor employed for producing two scraperbowls is no greater than that-heretofore employed in making one. The waste of material is inuch less than in manufacturing by the old method, in which the amount cut away to finish the end was considerable and failures-were frequent in produci'n blanks,

and the finished product is more sa able, being uniform in dimensions and havingabetter cutting edge.v Moreover, in the new method the sheets may be worked at a wider range of temperatures than in the old method, Where a certain temperature was indispensable to good work. In the new method the ed end to end, and during the shaping operation, stretching the metal of each bowl from the line of rospective separation of the bowls, whereby the quality of the metal at the edges produced by the separation, is improved.

2. The herein-described art of producing scraper-bowls or the like, which consists in shaping a sheet of metal between dies con-.

structed to produce two bowls connected at their front or cutting ends, and during such sha ing operation, stretching the metal of eac bowl from the line of prospective separation of the bowls to improve the metal at the ultimate cutting edges and dividing the blank thus produced.

3. The process of producing scraper-bowls which consists in stamping a sheet of metal between dies constructed to form two bowls connected at their open front or cutting ends, and during such stamping o eration, stretching the metal of each bow toward its rear end from the-line of connection between the bowls, and thereafter dividing the blank thus produced along such line of'connection.

4. The art of producing scraper-bowls or the like which consists in stamping a sheet of metal between dies constructed to form two such articles connected at their front or cutting ends, supporting the metal at such line of connection or line of prospective separation, before completion of the stamping operation whereby the metal is stretched from said line toward the opposite ends of the bowls and thereafter dividing the blank thus formed to roduce two bowl-blanks.

5. Theerein-described art of producing scraper-bowls or the like which consists in stamping a sheet of suitable metal between dies constructed to produce two such articles, connected at their cutting ends, whereby the metal of each pros ective bowl sustains the metal of the other liowl at said cutting edge and prospective line of separation, supporting the metal at said line of connection or prospective separation, during the latter part of t e stamping operation and finally separating-the blank thus formed into two bowls.

6. The hereindescribed improvement in the art of producing earth-scraper bowls or the like which consists in stamping a sheet of metal between dies constructed to form two bowls connected at their front or cutting ends along the line-of prospective separation 'and with the middle raised portion corresponding in position to such line, and stretching the metal over said raised portion during the stamping operation.

7. The herein-described improvement in the art of producing earth-scraper bowls or the like, which consists in stamping a sheet of metal between dies constructed to roduce two bowls connected at their open ont or cutting ends, sustaining the edges of the sheet at its ends and sides during the stamping operation, with a pressure that permits the metal to draw inward but which resists such drawing sufficiently to cause stretching of the metal in the ultimate bowls to be produced,

,and causing such stretching to take place from the line of connection or prospective r5 separation and thereafter separating the blank thus produced along said line.

The foregoing specification signed this 23d day of September, 1904.

THOS. H. STAGG.

In presence of W. A. )Lmsn, C. E. Born. 

